HMMT 十一月 2024 · 冲刺赛 · 第 22 题
HMMT November 2024 — Guts Round — Problem 22
题目详情
- [12] Suppose that a and b are positive integers such that gcd( a − b , ( a − b ) ) is not divisible by any perfect square except 1 . Given that 1 ≤ a − b ≤ 50 , compute the number of possible values of a − b across all such a, b . ̂
解析
- [12] Suppose that a and b are positive integers such that gcd( a − b , ( a − b ) ) is not divisible by any perfect square except 1. Given that 1 ≤ a − b ≤ 50 , compute the number of possible values of a − b across all such a, b . Proposed by: Srinivas Arun Answer: 23 Solution: Recall that a positive integer is squarefree if it is not divisible by any perfect square except